Lab homework

Lab 1 Report (10 points) There are five questions.

(2 points) Please read the following scenarios. Choose two. Answer the questions about each lab scenario. You should write in complete sentences.

Scenario 1. A student heated a volatile liquid by clamping a glass flask to a ring stand, pouring the liquid into the flask and lighting a Bunsen burner below the elevated flask. A moment later, the student sees a fire on the outside of the flask. Her lab notes and a few pieces of glassware were immediately next to this setup. a) What should the student do? b) What mistakes did the student make?

Scenario 2. Your lab experiment requires you to weigh about 2 grams of sodium bicarbonate. a) As you scoop out solid, some sticks to the spatula and falls on the tray of the balance. What should you do? Explain why you would take those actions. b) Your sample mass turns out to be 2.059 grams. Is this the actual mass of your sample?

Scenario 3. You get a text from your lab partner that he will be late. He arrives during the quiz and it turns out that he was unprepared for the experiment. The instructor tells the student that he will not be allowed to perform the experiment. What could be the possible reason(s) for the instructor’s decision?

Scenario 4. An experiment requires heating a liquid sample until a color change is observed. After 5 minutes, you and your partner don’t see any change. Your instructor indicates that this process could take as much as 20 min. Your partner leaves the room, without saying anything to you. While waiting for the color change of your sample, you start chatting with some classmates and turn to face them. a) What are at least three things that are (potentially) unsafe about this scenario?

(3 points) Find a Safety Data sheet (SDS) for a chemical you use every day, for example Head and Shoulders shampoo. Search on the internet for a SDS for that chemical. (You cannot choose Head and Shoulders shampoo). Submit it as an attachment to this lab report. Answer the following questions using the MSDS of that chemical.

            a. What is the chemical name listed on the SDS?

            b. Find Physical and Chemical Properties Section and list 2 physical properties and 2 chemical properties.

            c. What are the Handling and Storage Guidelines?

            d. List at least 2 things about the chemical that were interesting or surprising to you.

(2 points) Read the following statements. Label each as a hypothesis, a law or an observation.

          a. High barometric pressure precedes the onset of good weather.

          b. If my car will not start then it might mean my battery is dead.

          c. A CHEM 103 student records the temperature of a solution during lab.

(2 points) What SI Unit would you use to record the following measurements.

            a. The height of a person.

            b. The mass of a gold bar.

            c. The amount of sodium chloride added to a chemical reaction.

            d. The temperature of a sample of oxygen gas.

(1 point) Indicate the name and symbol of the metric prefix used to express the factor below.

            a. 106

            b. 000001

            c. 1000

            d. 01